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Micronics clamp on ultrasonic flow meters point to the future of flow measurement
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Micronics clamp on ultrasonic and non invasive flow meter overview presentation
<---Powerpoint Version
Micronics clamp on ultrasonic and non invasive flow meter overview
The Market
Technology & Operating Principals
Typical Configurations
Applications
Portable Ultrasonic Meters;
• The only realistic option for temporary applications
• One unit can measure any pipe diameter.
• Non intrusive
• No system downtime
Dedicated Meters;
• Non intrusive
• Low cost. Particularly on large pipes
• No moving parts
• Simple low cost installation
• No down time for maintenance
• No Pressure Drop - Energy efficient!
• Result is Low lifetime cost
Clamp-On flow meter theory
The Theory
• Time of Flight is suitable for clean liquids < 2% particles or contaminates
• Doppler is only suitable for contaminated or aerated liquids.
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The Micronics PF300 - an indispensable Transit Time flow meter for clean liquids
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The PDFM-4.0 uses the Doppler method and works with contaminated liquids including waste water
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Theory - Time of Flight
• Time of Flight Ultrasonic Meters measure the Transit Time of a beam of Ultrasound
• Flow velocity is calculated from the difference in time taken for the sound to travel either upstream against the flow or downstream.
• This time difference is extremely small for example 30 nanoseconds (30 x 10-9 sec) for a flow of 1 metre/sec in a 100mm pipe.
• In order to achieve accuracy particularly on smaller pipes with very low flows it is necessary to have a system that will resolve time differences of less than 0.5 nanosecond. Nominal accuracy for most Clamp-On systems is between 1-3% of flow rate above 0.3metres/sec.
Theory - Doppler
• When ultrasound hits a moving particle or gas bubble The reflected sound can be detected and the frequency shift measured.
• The frequency change is proportional to flow velocity which is converted to volumetric flow rate by multiplying by the cross sectional area of the pipe.
Clamp-On flow metering
Typical Configurations
Dedicated Clamp-On Flow and Heat
Meters
• Time of Flight meters for clean liquids
• Doppler portable meters for dirty liquids
• Mains, 24V DC, Battery Powered
• aM&T and BEMS compatible
• LCD or Graphics Displays
• Current, Pulse, RS 232/485 outputs
• Blind units pre-programmed for fit and forget applications
• Prices ranging from £800 to £3000.
• But Technology is driving prices down!
Portable Clamp-on instruments
• Time of Flight meters for clean liquids
• Doppler portable meters for dirty liquids
• LCD or Graphics Displays
• Battery Powered
• Data Logging
• Portable meters range in price from £600- £6000 depending on facilities offered and the level of performance.
• But Technology is driving prices down!
Clamp-On flow metering
Applications
• Chilled Water/LPHW/MTHW flow metering
• Thermal energy flow measurements when combined with diff temp measurement
• System commissioning
• Temporary monitoring (Trend/Consumption)
• Flow confirmation
• Effluent discharge measurements
• Plant Diagnostics & Leak detection
Improving energy efficiency using Clamp-on meters
• The low cost installation of a clamp-on meters to monitor flow and to identify instantly any change in performance a significant step towards ensuring energy efficient operation.
• Portable meters enable fast accurate energy audits.
• System balancing and defective in-line meter replacement can be performed without draining down.
• Leak Detection and water wastage can be simply tracked.
• Logging the use of Heat or coolth process and building services can now be achieved using clamp-on heat meters, driving down the cost of secondary metering.
• A Micronics Portaflow 300 was used to measure the flow of a 75kw pump that was operating into a control valve on the discharge side that was only 20% open.
• Obviously the pump was oversized and working inefficiently and was calculated that 66% of energy used was wasted.
• The pump was replaced with an 11kW unit at a capital cost of £1500.
• Energy costs were reduced from £5698 to £926 per year giving a payback period of approximately 4 months.
• Example of cost savings that can be achieved by selecting a clamp-on meter instead of a conventional inline meter for a Building Services retrofit application.
• A Borough Council now required to manage schools within its area was updating its plant monitoring in line with Part L2 of the Building Regulations.
• Heat delivered from a school central boiler house installation was due to be metered and quotations to supply and install Heat meters were requested from several companies offering in-line meters.
• The adoption of Clamp-On ultrasonic Heat Meters offered the Council the opportunity to save 40% of the cost of a similar in-line installation.
• Reduced disruption, no draining of pipe work, no residual venting problems, easier maintenance, and no pressure drop were all additional benefits that could not be matched by using an in-line meter.
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The Micronics U2000 and U100 series - Clamp-On, Non-Invasive and Cost Effective
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Conclusions
• Chilled Water/LPHW/MTHW flow metering
• Thermal energy flow measurements when combined with differential temperature measurement
• System commissioning
• Temporary monitoring (Trend/Consumption logging)
• Flow confirmation
• Effluent discharge measurements
• Plant Diagnostics & Leak detection
